xref: /linux/drivers/acpi/osl.c (revision 9ce7677cfd7cd871adb457c80bea3b581b839641)
1 /*
2  *  acpi_osl.c - OS-dependent functions ($Revision: 83 $)
3  *
4  *  Copyright (C) 2000       Andrew Henroid
5  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
6  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
7  *
8  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
9  *
10  *  This program is free software; you can redistribute it and/or modify
11  *  it under the terms of the GNU General Public License as published by
12  *  the Free Software Foundation; either version 2 of the License, or
13  *  (at your option) any later version.
14  *
15  *  This program is distributed in the hope that it will be useful,
16  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
17  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  *  GNU General Public License for more details.
19  *
20  *  You should have received a copy of the GNU General Public License
21  *  along with this program; if not, write to the Free Software
22  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
23  *
24  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
25  *
26  */
27 
28 #include <linux/config.h>
29 #include <linux/module.h>
30 #include <linux/kernel.h>
31 #include <linux/slab.h>
32 #include <linux/mm.h>
33 #include <linux/pci.h>
34 #include <linux/smp_lock.h>
35 #include <linux/interrupt.h>
36 #include <linux/kmod.h>
37 #include <linux/delay.h>
38 #include <linux/workqueue.h>
39 #include <linux/nmi.h>
40 #include <acpi/acpi.h>
41 #include <asm/io.h>
42 #include <acpi/acpi_bus.h>
43 #include <acpi/processor.h>
44 #include <asm/uaccess.h>
45 
46 #include <linux/efi.h>
47 
48 #define _COMPONENT		ACPI_OS_SERVICES
49 ACPI_MODULE_NAME("osl")
50 #define PREFIX		"ACPI: "
51 struct acpi_os_dpc {
52 	acpi_osd_exec_callback function;
53 	void *context;
54 };
55 
56 #ifdef CONFIG_ACPI_CUSTOM_DSDT
57 #include CONFIG_ACPI_CUSTOM_DSDT_FILE
58 #endif
59 
60 #ifdef ENABLE_DEBUGGER
61 #include <linux/kdb.h>
62 
63 /* stuff for debugger support */
64 int acpi_in_debugger;
65 EXPORT_SYMBOL(acpi_in_debugger);
66 
67 extern char line_buf[80];
68 #endif				/*ENABLE_DEBUGGER */
69 
70 int acpi_specific_hotkey_enabled = TRUE;
71 EXPORT_SYMBOL(acpi_specific_hotkey_enabled);
72 
73 static unsigned int acpi_irq_irq;
74 static acpi_osd_handler acpi_irq_handler;
75 static void *acpi_irq_context;
76 static struct workqueue_struct *kacpid_wq;
77 
78 acpi_status acpi_os_initialize(void)
79 {
80 	return AE_OK;
81 }
82 
83 acpi_status acpi_os_initialize1(void)
84 {
85 	/*
86 	 * Initialize PCI configuration space access, as we'll need to access
87 	 * it while walking the namespace (bus 0 and root bridges w/ _BBNs).
88 	 */
89 	if (!raw_pci_ops) {
90 		printk(KERN_ERR PREFIX
91 		       "Access to PCI configuration space unavailable\n");
92 		return AE_NULL_ENTRY;
93 	}
94 	kacpid_wq = create_singlethread_workqueue("kacpid");
95 	BUG_ON(!kacpid_wq);
96 
97 	return AE_OK;
98 }
99 
100 acpi_status acpi_os_terminate(void)
101 {
102 	if (acpi_irq_handler) {
103 		acpi_os_remove_interrupt_handler(acpi_irq_irq,
104 						 acpi_irq_handler);
105 	}
106 
107 	destroy_workqueue(kacpid_wq);
108 
109 	return AE_OK;
110 }
111 
112 void acpi_os_printf(const char *fmt, ...)
113 {
114 	va_list args;
115 	va_start(args, fmt);
116 	acpi_os_vprintf(fmt, args);
117 	va_end(args);
118 }
119 
120 EXPORT_SYMBOL(acpi_os_printf);
121 
122 void acpi_os_vprintf(const char *fmt, va_list args)
123 {
124 	static char buffer[512];
125 
126 	vsprintf(buffer, fmt, args);
127 
128 #ifdef ENABLE_DEBUGGER
129 	if (acpi_in_debugger) {
130 		kdb_printf("%s", buffer);
131 	} else {
132 		printk("%s", buffer);
133 	}
134 #else
135 	printk("%s", buffer);
136 #endif
137 }
138 
139 extern int acpi_in_resume;
140 void *acpi_os_allocate(acpi_size size)
141 {
142 	if (acpi_in_resume)
143 		return kmalloc(size, GFP_ATOMIC);
144 	else
145 		return kmalloc(size, GFP_KERNEL);
146 }
147 
148 void acpi_os_free(void *ptr)
149 {
150 	kfree(ptr);
151 }
152 
153 EXPORT_SYMBOL(acpi_os_free);
154 
155 acpi_status acpi_os_get_root_pointer(u32 flags, struct acpi_pointer *addr)
156 {
157 	if (efi_enabled) {
158 		addr->pointer_type = ACPI_PHYSICAL_POINTER;
159 		if (efi.acpi20)
160 			addr->pointer.physical =
161 			    (acpi_physical_address) virt_to_phys(efi.acpi20);
162 		else if (efi.acpi)
163 			addr->pointer.physical =
164 			    (acpi_physical_address) virt_to_phys(efi.acpi);
165 		else {
166 			printk(KERN_ERR PREFIX
167 			       "System description tables not found\n");
168 			return AE_NOT_FOUND;
169 		}
170 	} else {
171 		if (ACPI_FAILURE(acpi_find_root_pointer(flags, addr))) {
172 			printk(KERN_ERR PREFIX
173 			       "System description tables not found\n");
174 			return AE_NOT_FOUND;
175 		}
176 	}
177 
178 	return AE_OK;
179 }
180 
181 acpi_status
182 acpi_os_map_memory(acpi_physical_address phys, acpi_size size,
183 		   void __iomem ** virt)
184 {
185 	if (efi_enabled) {
186 		if (EFI_MEMORY_WB & efi_mem_attributes(phys)) {
187 			*virt = (void __iomem *)phys_to_virt(phys);
188 		} else {
189 			*virt = ioremap(phys, size);
190 		}
191 	} else {
192 		if (phys > ULONG_MAX) {
193 			printk(KERN_ERR PREFIX "Cannot map memory that high\n");
194 			return AE_BAD_PARAMETER;
195 		}
196 		/*
197 		 * ioremap checks to ensure this is in reserved space
198 		 */
199 		*virt = ioremap((unsigned long)phys, size);
200 	}
201 
202 	if (!*virt)
203 		return AE_NO_MEMORY;
204 
205 	return AE_OK;
206 }
207 
208 void acpi_os_unmap_memory(void __iomem * virt, acpi_size size)
209 {
210 	iounmap(virt);
211 }
212 
213 #ifdef ACPI_FUTURE_USAGE
214 acpi_status
215 acpi_os_get_physical_address(void *virt, acpi_physical_address * phys)
216 {
217 	if (!phys || !virt)
218 		return AE_BAD_PARAMETER;
219 
220 	*phys = virt_to_phys(virt);
221 
222 	return AE_OK;
223 }
224 #endif
225 
226 #define ACPI_MAX_OVERRIDE_LEN 100
227 
228 static char acpi_os_name[ACPI_MAX_OVERRIDE_LEN];
229 
230 acpi_status
231 acpi_os_predefined_override(const struct acpi_predefined_names *init_val,
232 			    acpi_string * new_val)
233 {
234 	if (!init_val || !new_val)
235 		return AE_BAD_PARAMETER;
236 
237 	*new_val = NULL;
238 	if (!memcmp(init_val->name, "_OS_", 4) && strlen(acpi_os_name)) {
239 		printk(KERN_INFO PREFIX "Overriding _OS definition to '%s'\n",
240 		       acpi_os_name);
241 		*new_val = acpi_os_name;
242 	}
243 
244 	return AE_OK;
245 }
246 
247 acpi_status
248 acpi_os_table_override(struct acpi_table_header * existing_table,
249 		       struct acpi_table_header ** new_table)
250 {
251 	if (!existing_table || !new_table)
252 		return AE_BAD_PARAMETER;
253 
254 #ifdef CONFIG_ACPI_CUSTOM_DSDT
255 	if (strncmp(existing_table->signature, "DSDT", 4) == 0)
256 		*new_table = (struct acpi_table_header *)AmlCode;
257 	else
258 		*new_table = NULL;
259 #else
260 	*new_table = NULL;
261 #endif
262 	return AE_OK;
263 }
264 
265 static irqreturn_t acpi_irq(int irq, void *dev_id, struct pt_regs *regs)
266 {
267 	return (*acpi_irq_handler) (acpi_irq_context) ? IRQ_HANDLED : IRQ_NONE;
268 }
269 
270 acpi_status
271 acpi_os_install_interrupt_handler(u32 gsi, acpi_osd_handler handler,
272 				  void *context)
273 {
274 	unsigned int irq;
275 
276 	/*
277 	 * Ignore the GSI from the core, and use the value in our copy of the
278 	 * FADT. It may not be the same if an interrupt source override exists
279 	 * for the SCI.
280 	 */
281 	gsi = acpi_fadt.sci_int;
282 	if (acpi_gsi_to_irq(gsi, &irq) < 0) {
283 		printk(KERN_ERR PREFIX "SCI (ACPI GSI %d) not registered\n",
284 		       gsi);
285 		return AE_OK;
286 	}
287 
288 	acpi_irq_handler = handler;
289 	acpi_irq_context = context;
290 	if (request_irq(irq, acpi_irq, SA_SHIRQ, "acpi", acpi_irq)) {
291 		printk(KERN_ERR PREFIX "SCI (IRQ%d) allocation failed\n", irq);
292 		return AE_NOT_ACQUIRED;
293 	}
294 	acpi_irq_irq = irq;
295 
296 	return AE_OK;
297 }
298 
299 acpi_status acpi_os_remove_interrupt_handler(u32 irq, acpi_osd_handler handler)
300 {
301 	if (irq) {
302 		free_irq(irq, acpi_irq);
303 		acpi_irq_handler = NULL;
304 		acpi_irq_irq = 0;
305 	}
306 
307 	return AE_OK;
308 }
309 
310 /*
311  * Running in interpreter thread context, safe to sleep
312  */
313 
314 void acpi_os_sleep(acpi_integer ms)
315 {
316 	schedule_timeout_interruptible(msecs_to_jiffies(ms));
317 }
318 
319 EXPORT_SYMBOL(acpi_os_sleep);
320 
321 void acpi_os_stall(u32 us)
322 {
323 	while (us) {
324 		u32 delay = 1000;
325 
326 		if (delay > us)
327 			delay = us;
328 		udelay(delay);
329 		touch_nmi_watchdog();
330 		us -= delay;
331 	}
332 }
333 
334 EXPORT_SYMBOL(acpi_os_stall);
335 
336 /*
337  * Support ACPI 3.0 AML Timer operand
338  * Returns 64-bit free-running, monotonically increasing timer
339  * with 100ns granularity
340  */
341 u64 acpi_os_get_timer(void)
342 {
343 	static u64 t;
344 
345 #ifdef	CONFIG_HPET
346 	/* TBD: use HPET if available */
347 #endif
348 
349 #ifdef	CONFIG_X86_PM_TIMER
350 	/* TBD: default to PM timer if HPET was not available */
351 #endif
352 	if (!t)
353 		printk(KERN_ERR PREFIX "acpi_os_get_timer() TBD\n");
354 
355 	return ++t;
356 }
357 
358 acpi_status acpi_os_read_port(acpi_io_address port, u32 * value, u32 width)
359 {
360 	u32 dummy;
361 
362 	if (!value)
363 		value = &dummy;
364 
365 	switch (width) {
366 	case 8:
367 		*(u8 *) value = inb(port);
368 		break;
369 	case 16:
370 		*(u16 *) value = inw(port);
371 		break;
372 	case 32:
373 		*(u32 *) value = inl(port);
374 		break;
375 	default:
376 		BUG();
377 	}
378 
379 	return AE_OK;
380 }
381 
382 EXPORT_SYMBOL(acpi_os_read_port);
383 
384 acpi_status acpi_os_write_port(acpi_io_address port, u32 value, u32 width)
385 {
386 	switch (width) {
387 	case 8:
388 		outb(value, port);
389 		break;
390 	case 16:
391 		outw(value, port);
392 		break;
393 	case 32:
394 		outl(value, port);
395 		break;
396 	default:
397 		BUG();
398 	}
399 
400 	return AE_OK;
401 }
402 
403 EXPORT_SYMBOL(acpi_os_write_port);
404 
405 acpi_status
406 acpi_os_read_memory(acpi_physical_address phys_addr, u32 * value, u32 width)
407 {
408 	u32 dummy;
409 	void __iomem *virt_addr;
410 	int iomem = 0;
411 
412 	if (efi_enabled) {
413 		if (EFI_MEMORY_WB & efi_mem_attributes(phys_addr)) {
414 			/* HACK ALERT! We can use readb/w/l on real memory too.. */
415 			virt_addr = (void __iomem *)phys_to_virt(phys_addr);
416 		} else {
417 			iomem = 1;
418 			virt_addr = ioremap(phys_addr, width);
419 		}
420 	} else
421 		virt_addr = (void __iomem *)phys_to_virt(phys_addr);
422 	if (!value)
423 		value = &dummy;
424 
425 	switch (width) {
426 	case 8:
427 		*(u8 *) value = readb(virt_addr);
428 		break;
429 	case 16:
430 		*(u16 *) value = readw(virt_addr);
431 		break;
432 	case 32:
433 		*(u32 *) value = readl(virt_addr);
434 		break;
435 	default:
436 		BUG();
437 	}
438 
439 	if (efi_enabled) {
440 		if (iomem)
441 			iounmap(virt_addr);
442 	}
443 
444 	return AE_OK;
445 }
446 
447 acpi_status
448 acpi_os_write_memory(acpi_physical_address phys_addr, u32 value, u32 width)
449 {
450 	void __iomem *virt_addr;
451 	int iomem = 0;
452 
453 	if (efi_enabled) {
454 		if (EFI_MEMORY_WB & efi_mem_attributes(phys_addr)) {
455 			/* HACK ALERT! We can use writeb/w/l on real memory too */
456 			virt_addr = (void __iomem *)phys_to_virt(phys_addr);
457 		} else {
458 			iomem = 1;
459 			virt_addr = ioremap(phys_addr, width);
460 		}
461 	} else
462 		virt_addr = (void __iomem *)phys_to_virt(phys_addr);
463 
464 	switch (width) {
465 	case 8:
466 		writeb(value, virt_addr);
467 		break;
468 	case 16:
469 		writew(value, virt_addr);
470 		break;
471 	case 32:
472 		writel(value, virt_addr);
473 		break;
474 	default:
475 		BUG();
476 	}
477 
478 	if (iomem)
479 		iounmap(virt_addr);
480 
481 	return AE_OK;
482 }
483 
484 acpi_status
485 acpi_os_read_pci_configuration(struct acpi_pci_id * pci_id, u32 reg,
486 			       void *value, u32 width)
487 {
488 	int result, size;
489 
490 	if (!value)
491 		return AE_BAD_PARAMETER;
492 
493 	switch (width) {
494 	case 8:
495 		size = 1;
496 		break;
497 	case 16:
498 		size = 2;
499 		break;
500 	case 32:
501 		size = 4;
502 		break;
503 	default:
504 		return AE_ERROR;
505 	}
506 
507 	BUG_ON(!raw_pci_ops);
508 
509 	result = raw_pci_ops->read(pci_id->segment, pci_id->bus,
510 				   PCI_DEVFN(pci_id->device, pci_id->function),
511 				   reg, size, value);
512 
513 	return (result ? AE_ERROR : AE_OK);
514 }
515 
516 EXPORT_SYMBOL(acpi_os_read_pci_configuration);
517 
518 acpi_status
519 acpi_os_write_pci_configuration(struct acpi_pci_id * pci_id, u32 reg,
520 				acpi_integer value, u32 width)
521 {
522 	int result, size;
523 
524 	switch (width) {
525 	case 8:
526 		size = 1;
527 		break;
528 	case 16:
529 		size = 2;
530 		break;
531 	case 32:
532 		size = 4;
533 		break;
534 	default:
535 		return AE_ERROR;
536 	}
537 
538 	BUG_ON(!raw_pci_ops);
539 
540 	result = raw_pci_ops->write(pci_id->segment, pci_id->bus,
541 				    PCI_DEVFN(pci_id->device, pci_id->function),
542 				    reg, size, value);
543 
544 	return (result ? AE_ERROR : AE_OK);
545 }
546 
547 /* TODO: Change code to take advantage of driver model more */
548 static void acpi_os_derive_pci_id_2(acpi_handle rhandle,	/* upper bound  */
549 				    acpi_handle chandle,	/* current node */
550 				    struct acpi_pci_id **id,
551 				    int *is_bridge, u8 * bus_number)
552 {
553 	acpi_handle handle;
554 	struct acpi_pci_id *pci_id = *id;
555 	acpi_status status;
556 	unsigned long temp;
557 	acpi_object_type type;
558 	u8 tu8;
559 
560 	acpi_get_parent(chandle, &handle);
561 	if (handle != rhandle) {
562 		acpi_os_derive_pci_id_2(rhandle, handle, &pci_id, is_bridge,
563 					bus_number);
564 
565 		status = acpi_get_type(handle, &type);
566 		if ((ACPI_FAILURE(status)) || (type != ACPI_TYPE_DEVICE))
567 			return;
568 
569 		status =
570 		    acpi_evaluate_integer(handle, METHOD_NAME__ADR, NULL,
571 					  &temp);
572 		if (ACPI_SUCCESS(status)) {
573 			pci_id->device = ACPI_HIWORD(ACPI_LODWORD(temp));
574 			pci_id->function = ACPI_LOWORD(ACPI_LODWORD(temp));
575 
576 			if (*is_bridge)
577 				pci_id->bus = *bus_number;
578 
579 			/* any nicer way to get bus number of bridge ? */
580 			status =
581 			    acpi_os_read_pci_configuration(pci_id, 0x0e, &tu8,
582 							   8);
583 			if (ACPI_SUCCESS(status)
584 			    && ((tu8 & 0x7f) == 1 || (tu8 & 0x7f) == 2)) {
585 				status =
586 				    acpi_os_read_pci_configuration(pci_id, 0x18,
587 								   &tu8, 8);
588 				if (!ACPI_SUCCESS(status)) {
589 					/* Certainly broken...  FIX ME */
590 					return;
591 				}
592 				*is_bridge = 1;
593 				pci_id->bus = tu8;
594 				status =
595 				    acpi_os_read_pci_configuration(pci_id, 0x19,
596 								   &tu8, 8);
597 				if (ACPI_SUCCESS(status)) {
598 					*bus_number = tu8;
599 				}
600 			} else
601 				*is_bridge = 0;
602 		}
603 	}
604 }
605 
606 void acpi_os_derive_pci_id(acpi_handle rhandle,	/* upper bound  */
607 			   acpi_handle chandle,	/* current node */
608 			   struct acpi_pci_id **id)
609 {
610 	int is_bridge = 1;
611 	u8 bus_number = (*id)->bus;
612 
613 	acpi_os_derive_pci_id_2(rhandle, chandle, id, &is_bridge, &bus_number);
614 }
615 
616 static void acpi_os_execute_deferred(void *context)
617 {
618 	struct acpi_os_dpc *dpc = NULL;
619 
620 	ACPI_FUNCTION_TRACE("os_execute_deferred");
621 
622 	dpc = (struct acpi_os_dpc *)context;
623 	if (!dpc) {
624 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid (NULL) context.\n"));
625 		return_VOID;
626 	}
627 
628 	dpc->function(dpc->context);
629 
630 	kfree(dpc);
631 
632 	return_VOID;
633 }
634 
635 acpi_status
636 acpi_os_queue_for_execution(u32 priority,
637 			    acpi_osd_exec_callback function, void *context)
638 {
639 	acpi_status status = AE_OK;
640 	struct acpi_os_dpc *dpc;
641 	struct work_struct *task;
642 
643 	ACPI_FUNCTION_TRACE("os_queue_for_execution");
644 
645 	ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
646 			  "Scheduling function [%p(%p)] for deferred execution.\n",
647 			  function, context));
648 
649 	if (!function)
650 		return_ACPI_STATUS(AE_BAD_PARAMETER);
651 
652 	/*
653 	 * Allocate/initialize DPC structure.  Note that this memory will be
654 	 * freed by the callee.  The kernel handles the tq_struct list  in a
655 	 * way that allows us to also free its memory inside the callee.
656 	 * Because we may want to schedule several tasks with different
657 	 * parameters we can't use the approach some kernel code uses of
658 	 * having a static tq_struct.
659 	 * We can save time and code by allocating the DPC and tq_structs
660 	 * from the same memory.
661 	 */
662 
663 	dpc =
664 	    kmalloc(sizeof(struct acpi_os_dpc) + sizeof(struct work_struct),
665 		    GFP_ATOMIC);
666 	if (!dpc)
667 		return_ACPI_STATUS(AE_NO_MEMORY);
668 
669 	dpc->function = function;
670 	dpc->context = context;
671 
672 	task = (void *)(dpc + 1);
673 	INIT_WORK(task, acpi_os_execute_deferred, (void *)dpc);
674 
675 	if (!queue_work(kacpid_wq, task)) {
676 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
677 				  "Call to queue_work() failed.\n"));
678 		kfree(dpc);
679 		status = AE_ERROR;
680 	}
681 
682 	return_ACPI_STATUS(status);
683 }
684 
685 EXPORT_SYMBOL(acpi_os_queue_for_execution);
686 
687 void acpi_os_wait_events_complete(void *context)
688 {
689 	flush_workqueue(kacpid_wq);
690 }
691 
692 EXPORT_SYMBOL(acpi_os_wait_events_complete);
693 
694 /*
695  * Allocate the memory for a spinlock and initialize it.
696  */
697 acpi_status acpi_os_create_lock(acpi_handle * out_handle)
698 {
699 	spinlock_t *lock_ptr;
700 
701 	ACPI_FUNCTION_TRACE("os_create_lock");
702 
703 	lock_ptr = acpi_os_allocate(sizeof(spinlock_t));
704 
705 	spin_lock_init(lock_ptr);
706 
707 	ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Creating spinlock[%p].\n", lock_ptr));
708 
709 	*out_handle = lock_ptr;
710 
711 	return_ACPI_STATUS(AE_OK);
712 }
713 
714 /*
715  * Deallocate the memory for a spinlock.
716  */
717 void acpi_os_delete_lock(acpi_handle handle)
718 {
719 	ACPI_FUNCTION_TRACE("os_create_lock");
720 
721 	ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Deleting spinlock[%p].\n", handle));
722 
723 	acpi_os_free(handle);
724 
725 	return_VOID;
726 }
727 
728 acpi_status
729 acpi_os_create_semaphore(u32 max_units, u32 initial_units, acpi_handle * handle)
730 {
731 	struct semaphore *sem = NULL;
732 
733 	ACPI_FUNCTION_TRACE("os_create_semaphore");
734 
735 	sem = acpi_os_allocate(sizeof(struct semaphore));
736 	if (!sem)
737 		return_ACPI_STATUS(AE_NO_MEMORY);
738 	memset(sem, 0, sizeof(struct semaphore));
739 
740 	sema_init(sem, initial_units);
741 
742 	*handle = (acpi_handle *) sem;
743 
744 	ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Creating semaphore[%p|%d].\n",
745 			  *handle, initial_units));
746 
747 	return_ACPI_STATUS(AE_OK);
748 }
749 
750 EXPORT_SYMBOL(acpi_os_create_semaphore);
751 
752 /*
753  * TODO: A better way to delete semaphores?  Linux doesn't have a
754  * 'delete_semaphore()' function -- may result in an invalid
755  * pointer dereference for non-synchronized consumers.	Should
756  * we at least check for blocked threads and signal/cancel them?
757  */
758 
759 acpi_status acpi_os_delete_semaphore(acpi_handle handle)
760 {
761 	struct semaphore *sem = (struct semaphore *)handle;
762 
763 	ACPI_FUNCTION_TRACE("os_delete_semaphore");
764 
765 	if (!sem)
766 		return_ACPI_STATUS(AE_BAD_PARAMETER);
767 
768 	ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Deleting semaphore[%p].\n", handle));
769 
770 	acpi_os_free(sem);
771 	sem = NULL;
772 
773 	return_ACPI_STATUS(AE_OK);
774 }
775 
776 EXPORT_SYMBOL(acpi_os_delete_semaphore);
777 
778 /*
779  * TODO: The kernel doesn't have a 'down_timeout' function -- had to
780  * improvise.  The process is to sleep for one scheduler quantum
781  * until the semaphore becomes available.  Downside is that this
782  * may result in starvation for timeout-based waits when there's
783  * lots of semaphore activity.
784  *
785  * TODO: Support for units > 1?
786  */
787 acpi_status acpi_os_wait_semaphore(acpi_handle handle, u32 units, u16 timeout)
788 {
789 	acpi_status status = AE_OK;
790 	struct semaphore *sem = (struct semaphore *)handle;
791 	int ret = 0;
792 
793 	ACPI_FUNCTION_TRACE("os_wait_semaphore");
794 
795 	if (!sem || (units < 1))
796 		return_ACPI_STATUS(AE_BAD_PARAMETER);
797 
798 	if (units > 1)
799 		return_ACPI_STATUS(AE_SUPPORT);
800 
801 	ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Waiting for semaphore[%p|%d|%d]\n",
802 			  handle, units, timeout));
803 
804 	if (in_atomic())
805 		timeout = 0;
806 
807 	switch (timeout) {
808 		/*
809 		 * No Wait:
810 		 * --------
811 		 * A zero timeout value indicates that we shouldn't wait - just
812 		 * acquire the semaphore if available otherwise return AE_TIME
813 		 * (a.k.a. 'would block').
814 		 */
815 	case 0:
816 		if (down_trylock(sem))
817 			status = AE_TIME;
818 		break;
819 
820 		/*
821 		 * Wait Indefinitely:
822 		 * ------------------
823 		 */
824 	case ACPI_WAIT_FOREVER:
825 		down(sem);
826 		break;
827 
828 		/*
829 		 * Wait w/ Timeout:
830 		 * ----------------
831 		 */
832 	default:
833 		// TODO: A better timeout algorithm?
834 		{
835 			int i = 0;
836 			static const int quantum_ms = 1000 / HZ;
837 
838 			ret = down_trylock(sem);
839 			for (i = timeout; (i > 0 && ret < 0); i -= quantum_ms) {
840 				schedule_timeout_interruptible(1);
841 				ret = down_trylock(sem);
842 			}
843 
844 			if (ret != 0)
845 				status = AE_TIME;
846 		}
847 		break;
848 	}
849 
850 	if (ACPI_FAILURE(status)) {
851 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
852 				  "Failed to acquire semaphore[%p|%d|%d], %s\n",
853 				  handle, units, timeout,
854 				  acpi_format_exception(status)));
855 	} else {
856 		ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
857 				  "Acquired semaphore[%p|%d|%d]\n", handle,
858 				  units, timeout));
859 	}
860 
861 	return_ACPI_STATUS(status);
862 }
863 
864 EXPORT_SYMBOL(acpi_os_wait_semaphore);
865 
866 /*
867  * TODO: Support for units > 1?
868  */
869 acpi_status acpi_os_signal_semaphore(acpi_handle handle, u32 units)
870 {
871 	struct semaphore *sem = (struct semaphore *)handle;
872 
873 	ACPI_FUNCTION_TRACE("os_signal_semaphore");
874 
875 	if (!sem || (units < 1))
876 		return_ACPI_STATUS(AE_BAD_PARAMETER);
877 
878 	if (units > 1)
879 		return_ACPI_STATUS(AE_SUPPORT);
880 
881 	ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Signaling semaphore[%p|%d]\n", handle,
882 			  units));
883 
884 	up(sem);
885 
886 	return_ACPI_STATUS(AE_OK);
887 }
888 
889 EXPORT_SYMBOL(acpi_os_signal_semaphore);
890 
891 #ifdef ACPI_FUTURE_USAGE
892 u32 acpi_os_get_line(char *buffer)
893 {
894 
895 #ifdef ENABLE_DEBUGGER
896 	if (acpi_in_debugger) {
897 		u32 chars;
898 
899 		kdb_read(buffer, sizeof(line_buf));
900 
901 		/* remove the CR kdb includes */
902 		chars = strlen(buffer) - 1;
903 		buffer[chars] = '\0';
904 	}
905 #endif
906 
907 	return 0;
908 }
909 #endif				/*  ACPI_FUTURE_USAGE  */
910 
911 /* Assumes no unreadable holes inbetween */
912 u8 acpi_os_readable(void *ptr, acpi_size len)
913 {
914 #if defined(__i386__) || defined(__x86_64__)
915 	char tmp;
916 	return !__get_user(tmp, (char __user *)ptr)
917 	    && !__get_user(tmp, (char __user *)ptr + len - 1);
918 #endif
919 	return 1;
920 }
921 
922 #ifdef ACPI_FUTURE_USAGE
923 u8 acpi_os_writable(void *ptr, acpi_size len)
924 {
925 	/* could do dummy write (racy) or a kernel page table lookup.
926 	   The later may be difficult at early boot when kmap doesn't work yet. */
927 	return 1;
928 }
929 #endif
930 
931 u32 acpi_os_get_thread_id(void)
932 {
933 	if (!in_atomic())
934 		return current->pid;
935 
936 	return 0;
937 }
938 
939 acpi_status acpi_os_signal(u32 function, void *info)
940 {
941 	switch (function) {
942 	case ACPI_SIGNAL_FATAL:
943 		printk(KERN_ERR PREFIX "Fatal opcode executed\n");
944 		break;
945 	case ACPI_SIGNAL_BREAKPOINT:
946 		/*
947 		 * AML Breakpoint
948 		 * ACPI spec. says to treat it as a NOP unless
949 		 * you are debugging.  So if/when we integrate
950 		 * AML debugger into the kernel debugger its
951 		 * hook will go here.  But until then it is
952 		 * not useful to print anything on breakpoints.
953 		 */
954 		break;
955 	default:
956 		break;
957 	}
958 
959 	return AE_OK;
960 }
961 
962 EXPORT_SYMBOL(acpi_os_signal);
963 
964 static int __init acpi_os_name_setup(char *str)
965 {
966 	char *p = acpi_os_name;
967 	int count = ACPI_MAX_OVERRIDE_LEN - 1;
968 
969 	if (!str || !*str)
970 		return 0;
971 
972 	for (; count-- && str && *str; str++) {
973 		if (isalnum(*str) || *str == ' ' || *str == ':')
974 			*p++ = *str;
975 		else if (*str == '\'' || *str == '"')
976 			continue;
977 		else
978 			break;
979 	}
980 	*p = 0;
981 
982 	return 1;
983 
984 }
985 
986 __setup("acpi_os_name=", acpi_os_name_setup);
987 
988 /*
989  * _OSI control
990  * empty string disables _OSI
991  * TBD additional string adds to _OSI
992  */
993 static int __init acpi_osi_setup(char *str)
994 {
995 	if (str == NULL || *str == '\0') {
996 		printk(KERN_INFO PREFIX "_OSI method disabled\n");
997 		acpi_gbl_create_osi_method = FALSE;
998 	} else {
999 		/* TBD */
1000 		printk(KERN_ERR PREFIX "_OSI additional string ignored -- %s\n",
1001 		       str);
1002 	}
1003 
1004 	return 1;
1005 }
1006 
1007 __setup("acpi_osi=", acpi_osi_setup);
1008 
1009 /* enable serialization to combat AE_ALREADY_EXISTS errors */
1010 static int __init acpi_serialize_setup(char *str)
1011 {
1012 	printk(KERN_INFO PREFIX "serialize enabled\n");
1013 
1014 	acpi_gbl_all_methods_serialized = TRUE;
1015 
1016 	return 1;
1017 }
1018 
1019 __setup("acpi_serialize", acpi_serialize_setup);
1020 
1021 /*
1022  * Wake and Run-Time GPES are expected to be separate.
1023  * We disable wake-GPEs at run-time to prevent spurious
1024  * interrupts.
1025  *
1026  * However, if a system exists that shares Wake and
1027  * Run-time events on the same GPE this flag is available
1028  * to tell Linux to keep the wake-time GPEs enabled at run-time.
1029  */
1030 static int __init acpi_wake_gpes_always_on_setup(char *str)
1031 {
1032 	printk(KERN_INFO PREFIX "wake GPEs not disabled\n");
1033 
1034 	acpi_gbl_leave_wake_gpes_disabled = FALSE;
1035 
1036 	return 1;
1037 }
1038 
1039 __setup("acpi_wake_gpes_always_on", acpi_wake_gpes_always_on_setup);
1040 
1041 static int __init acpi_hotkey_setup(char *str)
1042 {
1043 	acpi_specific_hotkey_enabled = FALSE;
1044 	return 1;
1045 }
1046 
1047 __setup("acpi_generic_hotkey", acpi_hotkey_setup);
1048 
1049 /*
1050  * max_cstate is defined in the base kernel so modules can
1051  * change it w/o depending on the state of the processor module.
1052  */
1053 unsigned int max_cstate = ACPI_PROCESSOR_MAX_POWER;
1054 
1055 EXPORT_SYMBOL(max_cstate);
1056 
1057 /*
1058  * Acquire a spinlock.
1059  *
1060  * handle is a pointer to the spinlock_t.
1061  * flags is *not* the result of save_flags - it is an ACPI-specific flag variable
1062  *   that indicates whether we are at interrupt level.
1063  */
1064 
1065 unsigned long acpi_os_acquire_lock(acpi_handle handle)
1066 {
1067 	unsigned long flags;
1068 	spin_lock_irqsave((spinlock_t *) handle, flags);
1069 	return flags;
1070 }
1071 
1072 /*
1073  * Release a spinlock. See above.
1074  */
1075 
1076 void acpi_os_release_lock(acpi_handle handle, unsigned long flags)
1077 {
1078 	spin_unlock_irqrestore((spinlock_t *) handle, flags);
1079 }
1080 
1081 #ifndef ACPI_USE_LOCAL_CACHE
1082 
1083 /*******************************************************************************
1084  *
1085  * FUNCTION:    acpi_os_create_cache
1086  *
1087  * PARAMETERS:  CacheName       - Ascii name for the cache
1088  *              ObjectSize      - Size of each cached object
1089  *              MaxDepth        - Maximum depth of the cache (in objects)
1090  *              ReturnCache     - Where the new cache object is returned
1091  *
1092  * RETURN:      Status
1093  *
1094  * DESCRIPTION: Create a cache object
1095  *
1096  ******************************************************************************/
1097 
1098 acpi_status
1099 acpi_os_create_cache(char *name, u16 size, u16 depth, acpi_cache_t ** cache)
1100 {
1101 	*cache = kmem_cache_create(name, size, 0, 0, NULL, NULL);
1102 	return AE_OK;
1103 }
1104 
1105 /*******************************************************************************
1106  *
1107  * FUNCTION:    acpi_os_purge_cache
1108  *
1109  * PARAMETERS:  Cache           - Handle to cache object
1110  *
1111  * RETURN:      Status
1112  *
1113  * DESCRIPTION: Free all objects within the requested cache.
1114  *
1115  ******************************************************************************/
1116 
1117 acpi_status acpi_os_purge_cache(acpi_cache_t * cache)
1118 {
1119 	(void)kmem_cache_shrink(cache);
1120 	return (AE_OK);
1121 }
1122 
1123 /*******************************************************************************
1124  *
1125  * FUNCTION:    acpi_os_delete_cache
1126  *
1127  * PARAMETERS:  Cache           - Handle to cache object
1128  *
1129  * RETURN:      Status
1130  *
1131  * DESCRIPTION: Free all objects within the requested cache and delete the
1132  *              cache object.
1133  *
1134  ******************************************************************************/
1135 
1136 acpi_status acpi_os_delete_cache(acpi_cache_t * cache)
1137 {
1138 	(void)kmem_cache_destroy(cache);
1139 	return (AE_OK);
1140 }
1141 
1142 /*******************************************************************************
1143  *
1144  * FUNCTION:    acpi_os_release_object
1145  *
1146  * PARAMETERS:  Cache       - Handle to cache object
1147  *              Object      - The object to be released
1148  *
1149  * RETURN:      None
1150  *
1151  * DESCRIPTION: Release an object to the specified cache.  If cache is full,
1152  *              the object is deleted.
1153  *
1154  ******************************************************************************/
1155 
1156 acpi_status acpi_os_release_object(acpi_cache_t * cache, void *object)
1157 {
1158 	kmem_cache_free(cache, object);
1159 	return (AE_OK);
1160 }
1161 
1162 /*******************************************************************************
1163  *
1164  * FUNCTION:    acpi_os_acquire_object
1165  *
1166  * PARAMETERS:  Cache           - Handle to cache object
1167  *              ReturnObject    - Where the object is returned
1168  *
1169  * RETURN:      Status
1170  *
1171  * DESCRIPTION: Get an object from the specified cache.  If cache is empty,
1172  *              the object is allocated.
1173  *
1174  ******************************************************************************/
1175 
1176 void *acpi_os_acquire_object(acpi_cache_t * cache)
1177 {
1178 	void *object = kmem_cache_alloc(cache, GFP_KERNEL);
1179 	WARN_ON(!object);
1180 	return object;
1181 }
1182 
1183 #endif
1184